CVE-2026-31951

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc1 through 0.8.3-rc1, user-created MCP Model Context Protocol servers can include arbitrary HTTP headers that undergo credential placeholder substitution. An attacker can create a malicious MCP server with headers containin...

CVE-2026-31943

LibreChat is a ChatGPT clone with additional features. Prior to version 0.8.3, isPrivateIP in packages/api/src/auth/domain.ts fails to detect IPv4-mapped IPv6 addresses in their hex-normalized form, allowing any authenticated user to bypass SSRF protection and make the server issue HTTP requests ...

CVE-2026-31951 LibreChat's MCP Server Header Injection Enables OAuth Token Theft

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc1 through 0.8.3-rc1, user-created MCP Model Context Protocol servers can include arbitrary HTTP headers that undergo credential placeholder substitution. An attacker can create a malicious MCP server with headers containin...

CVE-2026-31951

Vulnerability summary : LibreChat’s MCP server feature (versions 0.8.2-rc1 to 0.8.3-rc1) allows arbitrary HTTP headers that undergo credential placeholder substitution. An attacker can host a malicious MCP server with headers like {{LIBRECHAT_OPENID_ACCESS_TOKEN}} to exfiltrate victims’ OAuth tok...

CVE-2026-31951 LibreChat's MCP Server Header Injection Enables OAuth Token Theft

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc1 through 0.8.3-rc1, user-created MCP Model Context Protocol servers can include arbitrary HTTP headers that undergo credential placeholder substitution. An attacker can create a malicious MCP server with headers containin...

CVE-2026-31951 LibreChat's MCP Server Header Injection Enables OAuth Token Theft

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc1 through 0.8.3-rc1, user-created MCP Model Context Protocol servers can include arbitrary HTTP headers that undergo credential placeholder substitution. An attacker can create a malicious MCP server with headers containin...

EUVD-2026-16769

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc1 through 0.8.3-rc1, user-created MCP Model Context Protocol servers can include arbitrary HTTP headers that undergo credential placeholder substitution. An attacker can create a malicious MCP server with headers containin...

CVE-2026-31951

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc1 through 0.8.3-rc1, user-created MCP Model Context Protocol servers can include arbitrary HTTP headers that undergo credential placeholder substitution. An attacker can create a malicious MCP server with headers containin...

CVE-2026-31950 LibreChat's IDOR in SSE Stream Subscription Allows Reading Other Users' Chats

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc2 through 0.8.2-rc3, the SSE streaming endpoint /api/agents/chat/stream/:streamId does not verify that the requesting user owns the stream. Any authenticated user who obtains or guesses a valid stream ID can subscribe and...

CVE-2026-31950 LibreChat's IDOR in SSE Stream Subscription Allows Reading Other Users' Chats

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc2 through 0.8.2-rc3, the SSE streaming endpoint /api/agents/chat/stream/:streamId does not verify that the requesting user owns the stream. Any authenticated user who obtains or guesses a valid stream ID can subscribe and...

CVE-2026-31950

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc2 through 0.8.2-rc3, the SSE streaming endpoint /api/agents/chat/stream/:streamId does not verify that the requesting user owns the stream. Any authenticated user who obtains or guesses a valid stream ID can subscribe and...

EUVD-2026-16767

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc2 through 0.8.2-rc3, the SSE streaming endpoint /api/agents/chat/stream/:streamId does not verify that the requesting user owns the stream. Any authenticated user who obtains or guesses a valid stream ID can subscribe and...

CVE-2026-31950 LibreChat's IDOR in SSE Stream Subscription Allows Reading Other Users' Chats

LibreChat is a ChatGPT clone with additional features. In versions 0.8.2-rc2 through 0.8.2-rc3, the SSE streaming endpoint /api/agents/chat/stream/:streamId does not verify that the requesting user owns the stream. Any authenticated user who obtains or guesses a valid stream ID can subscribe and...

CVE-2026-31950

LibreChat exposes an IDOR in SSE stream subscriptions. In versions 0.8.2-rc2 through 0.8.2-rc3, the endpoint /api/agents/chat/stream/:streamId does not verify stream ownership, allowing any authenticated user who guesses or obtains a valid streamId to subscribe and read another user’s real-time c...

EUVD-2026-16765

LibreChat is a ChatGPT clone with additional features. Versions 0.8.2-rc2 through 0.8.2 are vulnerable to a server-side request forgery SSRF attack when using agent actions or MCP. Although a previous SSRF vulnerability...

CVE-2026-31945

LibreChat is a ChatGPT clone with additional features. Versions 0.8.2-rc2 through 0.8.2 are vulnerable to a server-side request forgery SSRF attack when using agent actions or MCP. Although a previous SSRF vulnerability...

CVE-2026-31945 LibreChat Server-Side Request Forgery using DNS resolution

LibreChat is a ChatGPT clone with additional features. Versions 0.8.2-rc2 through 0.8.2 are vulnerable to a server-side request forgery SSRF attack when using agent actions or MCP. Although a previous SSRF vulnerability...

CVE-2026-31945

LibreChat (versions 0.8.2-rc2 to 0.8.2) is vulnerable to SSRF via DNS resolution in agent actions or MCP. The issue arises because prior fixes only added hostname validation and do not verify whether DNS results map to private IPs, allowing access to internal resources (e.g., internal RAG API or ...

EUVD-2026-16764

LibreChat is a ChatGPT clone with additional features. Prior to version 0.8.3, isPrivateIP in packages/api/src/auth/domain.ts fails to detect IPv4-mapped IPv6 addresses in their hex-normalized form, allowing any authenticated user to bypass SSRF protection and make the server issue HTTP requests ...

CVE-2026-31943 LibreChat has SSRF protection bypass via IPv4-mapped IPv6 normalization in isPrivateIP

LibreChat is a ChatGPT clone with additional features. Prior to version 0.8.3, isPrivateIP in packages/api/src/auth/domain.ts fails to detect IPv4-mapped IPv6 addresses in their hex-normalized form, allowing any authenticated user to bypass SSRF protection and make the server issue HTTP requests ...